{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T04:01:57Z","timestamp":1782273717624,"version":"3.54.5"},"reference-count":19,"publisher":"SAGE Publications","issue":"14","license":[{"start":{"date-parts":[[2015,10,8]],"date-time":"2015-10-08T00:00:00Z","timestamp":1444262400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Mult Scler"],"published-print":{"date-parts":[[2015,12]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Anti-JC virus antibody status is a risk factor for progressive multifocal leukoencephalopathy after natalizumab treatment in multiple sclerosis. Previous studies have used a cross-sectional approach to conclude that the presence and duration of natalizumab treatment does not influence anti-JCV Ab seropositivity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives:<\/jats:title>\n                    <jats:p>Using a longitudinal approach, we measured change in anti-JCV Ab results after natalizumab treatment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>Anti-JCV Ab results ( n = 1154) from the second-generation STRATIFY JCV\u2122 DxSelect\u2122 test were analysed from an observational cohort of MS patients on natalizumab ( n = 485; n = 340 with repeat testing; n = 657 repeat tests on natalizumab).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      Across sequential paired tests, seroconversion rate was greater than seroreversion rate (40\/364 (11.0%) versus 18\/293 (6.1%); p &lt; 0.05). Moreover, anti-JCV Ab index increased across longitudinal paired tests ( m\n                      <jats:sub>A\u2013B<\/jats:sub>\n                      0.102; paired t(656) = 5.0; p &lt; 0.0001). This magnitude of Ab level increase far exceeds that expected due to increasing age alone.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>Our data suggest that natalizumab therapy is associated with a significant and substantial increase in anti-JCV Ab index over time. Further work should focus on the underlying mechanisms of this phenomenon, and the clinical relevance to risk stratification.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/1352458515599681","type":"journal-article","created":{"date-parts":[[2015,10,8]],"date-time":"2015-10-08T21:29:31Z","timestamp":1444339771000},"page":"1833-1838","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":38,"title":["Anti-JC virus antibody titres increase over time with natalizumab treatment"],"prefix":"10.1177","volume":"21","author":[{"given":"J","family":"Raffel","sequence":"first","affiliation":[{"name":"Department of Medicine, Imperial College London, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"AR","family":"Gafson","sequence":"additional","affiliation":[{"name":"Department of Medicine, Imperial College London, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"O","family":"Malik","sequence":"additional","affiliation":[{"name":"Department of Medicine, Imperial College London, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Nicholas","sequence":"additional","affiliation":[{"name":"Department of Medicine, Imperial College London, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2015,10,8]]},"reference":[{"key":"bibr1-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa044396"},{"key":"bibr2-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa044397"},{"key":"bibr3-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1097\/NEN.0b013e31825caf2c"},{"key":"bibr4-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa051782"},{"key":"bibr5-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1177\/1352458511435105"},{"key":"bibr6-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1016\/j.jcv.2013.02.002"},{"key":"bibr7-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1002\/ana.24286"},{"key":"bibr8-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.0b013e3182583022"},{"key":"bibr9-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1177\/1352458513477925"},{"key":"bibr10-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1002\/ana.22606"},{"issue":"1","key":"bibr11-1352458515599681","volume":"78","author":"Bozic C","year":"2012","journal-title":"Neurology"},{"key":"bibr12-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1007\/s00415-012-6487-5"},{"key":"bibr13-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1177\/1352458513505353"},{"key":"bibr14-1352458515599681","volume-title":"Proceedings of the 22nd Conference Meeting of the European Neurological Society","author":"Lee P"},{"key":"bibr15-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.52.5.1072"},{"key":"bibr16-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.0b013e3181a8266f"},{"key":"bibr17-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa0904267"},{"key":"bibr18-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1007\/s11481-013-9496-y"},{"key":"bibr19-1352458515599681","doi-asserted-by":"publisher","DOI":"10.1001\/jamaneurol.2014.63"}],"container-title":["Multiple Sclerosis Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/1352458515599681","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/1352458515599681","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/1352458515599681","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T03:45:01Z","timestamp":1777693501000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/1352458515599681"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,10,8]]},"references-count":19,"journal-issue":{"issue":"14","published-print":{"date-parts":[[2015,12]]}},"alternative-id":["10.1177\/1352458515599681"],"URL":"https:\/\/doi.org\/10.1177\/1352458515599681","relation":{},"ISSN":["1352-4585","1477-0970"],"issn-type":[{"value":"1352-4585","type":"print"},{"value":"1477-0970","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,10,8]]}}}